Method and apparatus for backing-up electrotype shells



Sept. 2, 1958 e. w. BUNGAY METHOD AND APPARATUS FOR BACKING-UPELECTROTYPE SHELLS Filed Dec. 5, 1953 5 Sheets-Sheet 1 ATTORNEYS.

Sept. 2, 1958 G. w'. BUNGAY METHOD AND APPARATUS FOR BACKING-UPELECTROTYPE SHELLS 5 Sheets-Sheet 2 Filed Dec. 3, 1953 INVENTOR. 65mm:14 BUNGAY zz i fifza ATTORNEYS.

Sept. 2, 1958 a. w. BUNGAY METHOD AND APPARATUS FOR BACKING-UPELECTROTYPE SHELLS 5 Sheets-Sheet 3 Filed D90. 3, 1953 WATER COOLEDINVENTOR. GEORGE W. Bu/va/n NEYS.

Sept. 2, 1958 G. w. BUNGAY 2,849,768

METHOD AND APPARATUS FOR BACKING-UP ELECTRO'I'YPE sHEILLs 5 Sheets-Sheet4 Filed Dec.- 5, 1953 I QM. NW 3 Wm INVENTOR.

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n Y J Sept. 2, 1958 e. w. B'UNGAY METHOD AND APPARATUS FOR BACKING-UPELECTROTYPE SHELLS Filed Dec. 3, 195s 5 Sheets-Sheet 5 FIIIIIL W MSIR.WWMEQ A N A A A R.G. 4/ mw A, m M WW E m w W 6 Y/OVI B m A S ATTORNEYS.

United States PatentQ lVIETHOD AND APPARATUS FOR BACKING-UP ELECTROTYPESHELLS George Waldemar Bungay, New York, N. Y., assignor toElectrographic Corporation, New York, N. Y., a corporation of DelawareApplication December 3, 1953, Serial No. 395,995

5 Claims. (Cl. 22-58) The invention relates to a novel method andapparatus for .backing-up" electrotype shells for letter press printmg.

Heretofore great difficulty has been encountered in properly backing-upelectrotype shells for letterpress printing. In order to obtain a highquality impression from an electrotype shell the face of the shell mustbe unwarped. Due to the rapid changes in temperature to which the thincopper electrotype shells are subjected in the backing-up process, andto the difierence in thermal expansion between the shell and the backingmetal, a con siderable amount of warpage occurs which causes the face ofthe shell to be uneven, thereby requiring excessive work on the plate torender its face flat before it is madeready. Presently known methods andapparatus for backing-up electrotype shells do not completely preventthis warpage and large amounts of time and effort are required tocorrect the defects caused thereby, often to the serious injury of theprinting face.

In addition to the above-mentioned requirements it is also desirablethat the density of the backed-up shells be uniform, and that all of theplates be backed-up with only a slight excess of metal so as to preventoverfiow of the backing metal. In order to obtain such uniformity it ispresent practice to apply a considerable excess amount of backing metalto the shell and to shave the plate to the proper thickness afterward.This assures uniform thickness but also often introduces another stepinto the process. As a result of these additional'operations and becauseof other time consuming operations (i. e. hand pouring, slow cooling)present methods and apparatus for backing-up electrotype shells are timeconsuming and costly.

Accordingly, it is an object of the present invention to provide amethod for backing-up electrotype shells which avoids warpage of theelectrotype shell, produces substantially uniformly thick electrotypes,and produces the electrotype shells more quickly than presently knownmethods at lower cost, also avoiding the need for cleaning backing metalfrom the face of the shell or plate.

A further object of the invention is to provide apparatus which willperform the functions of the above method either automatically or undermanual control.

More specifically it is an object of the invention to provide a machinewhich will insure uniform heating of the electrotype shell prior toreceiving the molten backing metal. 1

Another object of the invention is to provide a ma- 2,849,768 7 PatentedSept. 2, 1958 ice A further object of the invention is to provide amachine which will rapidly solidify the backing metal after Otherobjects of the invention will be in part obvious and in part pointed outhereinafter.

The applicants method includes, briefly, placing an electrotype shellupon a supporting surface which is preferably heated but which need notbe, pressing downwardly upon the shell at a plurality of spaced pointsto hold the face of the shell in contact with the supporting surface,pouring the molten backing metal onto the shell and withdrawing thepressure after the pouring is complete. If

it is desired to speed the process a predetermined amount of air may bedirected at the shell to bring the molten metal to a plastic sandycondition. backed shell may be cooled by placing it upon a cooledsurface and pressure may be applied to the backed shell or plate toprevent warpage during cooling.

Applicants apparatus for carrying out the above method comprises a tablehaving a supporting surface for an electrotype shell preferably heatedfrom underneath by suitable heating means. A plurality of retractable,down- 1 wardly acting rods, or fingers, for exerting a downward pressureon the supporting surface at a plurality of individual points, arelocated above the supporting surface.

Suitable cooling means are also provided for rapidly I bringing thebacking metal to a plastic sandy state after it has beenpoured onto theshell, said means comprising a plurality of air tubes interspersed amongthe downwardly acting fingers and located directly above the supportingsurface for the electrotype shell. A conduit in the supporting structurefor the retractable fingers communicates the tubes with the output of ablower mounted atthe rear of the table. A pot for holding and heatingthe backing metal is preferably located immediately adjacent the tableand a pump is mounted on the pot and provided with a heated conduitleading to the supporting surface on the table to pump molten backingmetal onto an electrotype shell placed on the surface.

Applicants preferred apparatus also includes a press having a cooled,movable supporting surface for the backed electrotype shell.

type having a water cooled supporting surface mounted on the forwardportion thereof. Suitable controlmechanisms are provided to cause thecooled surface to carry the electrotype shell into the press portionwhere pressure is applied to the shell during the cooling operation.Other suitable control mechanisms are also provided for automaticallytiming the operation of the pump, the blower, the retractable fingers,the heating means for the supporting table andfor the hydraulic press.The pump timer control is constructed and indexed in such a manner thatit indicates the proper hydraulic pressure to be used for the amount ofmolten backing metal pumped onto the electrotype shell. The apparatusmay also be manually operated whenever such operation is desired.

It will be understood that the foregoing general de- 1 scription and thefollowing detailed description as well are exemplary and explanatory ofthe invention but are not restrictive thereof.

The accompanying drawings, referred to herein and constituting a parthereof, illustrate one form of ap- In addition, the

In the embodiment shown and described the press is of the variablepressure hydraulic In the drawings, in which similarreferencesnurneralsrefer to similar parts,

Figure 1 isa front elevation of the apparatus showing the generalarrangement of the various parts,

Figure 2 is a plan view, partly in section, taken along;

the line 2-2 in Fig. 1, of the supporting table showing a preferredarrangement of the air tubes amid the retractable fingers,

Figure 3. is a front view showing the face ofthe control mechanism forthe pump,

Figure'4 is a side elevation of the apparatus showing the arrangement ofthe blower apparatus, the actuating mechanism for the retractablefingers, and the path of the air from the blower to the air blast tubes,

Figure 5 is a perspective view of an electrotype shellprior to beingbacked-up.

Figures 6-9 illustrate the various steps of the applicants method ofbacking-up electrotype shells,

Figure 10 is the electrical control circuit diagram for the supporting,table apparatus, and

Figure 11 is the electrical control circuit diagram for the hydraulicpress apparatus.

Referring, now to the drawings for a detailed description of theapplicants method and apparatus and turning.

particularly to Figures 59 there is shown in Figure 5 an electrotypeshell 10 prior to the backing-up operation. Although the applicantsmethod may be utilized with any type of electrotype shell the type ofshell shown in Figure 5 is a type which is particularly suited for theapplicants method. In this type of shell, the edges 11 of the shell10-are bent upwardly so as to form a tray? like member, the outsidebottom of the tray being formed by the face of the shell and containingthe printing type which will be impressed upon the paper. In order toinsure a proper. bond between the inside bottom 12 of the shell 10 andthe backing metal which is to. be ap-- plied-thereto a suitable flux maybe applied to the inner surface of the shell, but this is not essential.Y

The shellv is placed upon a smooth perfectly flat supporting surface 20which is preferably, but not neces-' sarily, heated from underneath tomelt the flux on the innersurface thereof. I When the shell is placeduponthe supporting surface 20 downwardly acting pressure is applied at aplurality of individual points 22 uniformly.

operation has been completed the downwardly acting pressure is withdrawnand the heat under the supporting surface is reduced or discontinued.

.If it is desired to speed up the operation a predeterminedamount ofcooling air may be directed at the molten metal in the shell to quicklybring itto a'plastie If the molten backing metal is electro--- sandystate. type metal this.sandy condition will occur in the range of 510 to550 F. The stoppage of the air indicates to the operator that thebacking metal has been brought tell the operator to place the shell 10upon a cooled'supporting surface 25 to effect further cooling of theback? ing metal and shell while maintaining them against warpage. Acardboard sheet 26' may also be placed on the shell to form a backingtherefor. cooling operation a forceful, even pressure is applied on theentire surface of the shell by a resilient pad 'to preventthe shell fromwarping.

Even heating of the electrotype shell During the reduces the warp-.

4 age which would occur if the shell were unevenly heated. Theapplication of pressure to the shell at a number of individual pointsduring the heating and pouring operations holds the shell in properalignment, speeds up the heating of the shell and prevents any warpageof the shell from occurring. By predetermining the amount of moltenbacking metal to be poured into each shell the applicants metho'dprevents overflow, achieves uniform thickness, avoids' waste, and theadditionof the solidifying' and cooling stepsspeeds up the operation. Byapplying pressure to the shell during the cooling operation warpage inthis operation is also eliminated. The

end result is a product which is uniform and in perfect alignment;

In Figures 1-4, there is shown a preferred embodiment of an apparatusconstructed in accordance with the teachings of the applicants inventionand designed to carry out'the-method outlined. above. The apparatusincludesthree principal parts; a pot 30 for holding and heating thebacking metal, a supporting table 40 upon which the principal steps ofthe method are carried out and a press 70 in which the backed-upelectrotypeshell may be further cooled under pressure.

The supporting table 40 includes a supporting surface 41 for theelectrotype shell approximately waist high for the convenience of theoperator and finished so as to be perfectly flat and smooth. Underneaththesupporting surface 41 there is provided suitable heating means forheatingthe supporting surface. In the form of the invention shown theheating means comprises parallel series of gas burners 42 situated .ashort distance underneath the supporting surface. The burnerscommunicate with a gas header 43 mounted on the front of the supportingtable 40 and the entire area underneath the supporting surface isprovided with a pair ofchimneys 44 which direct the hot gases upwardlyand away from the apparatus. A pilot light 45 is provided to ignite thegasescaping from the burners, The heating apparatus is controlled bysuitable devices (to be described hereinafter) so as to be normally onexcept when cooling air is-being directed at the shell.

The table 40 is also provided with a plurality of rodlike retractablefingers mounted so as to be capable of exerting downwardly actingpressure uponthe support- '65 to the plastic sandy condition and acts asa signal toing surface 41. Each of the fingers is individually weighted-51' and yieldably mounted in a frame '52 in order to conform to anyirregularities in the electrotype shell 10. The terminal portions 53 ofthe fingers 50 are sharply.- pointed to minimize the amount of heatconducted away from the shell during the heating and pouring operations.The frame 52 is mounted to slide upon a pair'of parallel rods 54depending from an air header 55'locatedabove the supporting surface 41and is provided with a pin 56 at each end having a lever arm 57 pivotedthereon. Each leverarm is in turn pivoted at itsopposite end to suitablepins 58 mounted on the arms of a yoke 59. The yoke is pivotally mountedon a supporting column-60 located at the rearward portion of the tableand is actuated upwardly and downwardly by means of a hydraulic pistonand cylinder 61 secured to ghe-opposite end of the yoke 59 and pivotedon the base Interspersed among the fingers 50 area plurality of evenlyspaced air blast tubes 63 through which cooling air is directed at theelectrotype-shell 10. The tubes 63'are attachedto an air header 55 whichis mounted on the upper end of the supporting column 60 for the fingerstructure. The header 55 and the supporting column 60*are hollow so asto form a conduit 64 by which cooling air may be conveyed to the airblast tubes 63. A centrifugal blower 65 is locatedbehind the supportingtable 40 and is so positioned that its discharge conduit 66 communicateswith the bottom of the hollow'sup porting structure-andcommunicatesthrough the column 60 and the air header S5-with'the air-tubes.

A pot 30 for holding and heating the backing metal is preferably locatedimmediately adjacent the supporting table. A motor driven pump 31 ismounted on the pot for pumping molten metal to the supporting surface 41on the table. To this end, the casing 32 of the pump 31 is provided witha long discharge conduit 33 terminating in a nozzle 34 a short distanceabove the supporting surface 41 of the table 40. In order to prevent themolten metal from being cooled during its passage through the conduit 33a series of gas burners 35, communicating with the main gas header 43,are provided at spaced intervals along the discharge conduit.

Immediately adjacent the table 40, on a side opposite to that of the pot30, there is provided a variable pressure hydraulic press 70 having awater cooled platen, or supporting surface 71, for the shell. Theplaten, or supporting surface 71, comprises the forward portion of theapparatus while the press occupies the rearward portion. water-cooledresilient pad 90 preferably made of silicone rubber. The platen ismovable rearwardly so as to lie within the plane of the ram 72 and theresilient pad 90 of the hydraulic press (Fig. 11). To this end, thewater cooled platen 71 is provided with a rod 73 having an elongatedslot 74 to receive a rectangular shaft 75 mounted on a pinion 76. Ahydraulically actuated rack 77 engages the pinion 76 to rotate thepinion and move the platen 71 rearwardly into the path of the hydraulicram 72. A spring biased solenoid actuated valve 78 controls the flow ofhydraulicfiuid to the actuating piston 79 for the rack 77. A similarspring biased solenoid actuated valve 80 controls the flow of hydraulicfluid to the ram piston 81. Each of the valves is controlled by suitableelectrical mechanism (to be described hereinafter). A temperature gauge82 for indicating The press comprises a ram 72 and an upper,-

the temperature of the metal in the pot 30 is mounted on the outerportion of the press 70. A gauge 83 for indicating the hydraulicpressure of the system, is also mounted on the press and a manuallyoperable handle 84 is provided at the front of the press by which thepressure of the press may be varied.

In order to render the apparatus capable of use with various sizes ofelectrotype shells a timing device 36 is mounted on the press 70 bywhich the output of the pump 31 may be varied. Since the amount ofpressure to be applied to the shell during the cooling operation variesin accordance with the size of the shell being backed and, hence, withthe amount of metal poured onto the shell, the face of the pump timingdevice 36 is provided with a dual set of calibrations 3738 (sec Fig. 3).The inner set 37 of calibrations represent time in seconds while theouter set 38 of calibrations represent pressure in tons. Prior tostarting the apparatus the operator sets the timer pointer 39 accordingto the area of the shell which is to be backed-up and reads off thecorresponding pressure for the hydraulic press which he sets by means ofthe handle 84 and the gauge 83. The apparatus is then ready to start thecycle of operation.

The operation of the apparatus is as follows: the tray shapedelectrotype shell 10 is first placed upon the supporting surface 41 ofthe table 40, the gas burners 42 are ignited and the supporting surfaceand the electrotype shell are heated from below. At the same time theoperator pushes button 1 thereby causing the fingers 50 to movedownwardly and exert an evenly distributed pressure on the shell to holdthe shell in firm and intimate contact with the supporting surface. Whenthe flux is in proper condition to receive the backing metal, theoperator pushes button 2 which starts the pump 31 and causes thepredetermined amount of backing metal 24 to be poured onto theelectrotype shell. When the pouring operation is completed the fingers50 are automatically retracted and the gas automatically turned off. Atthe same'time, the blower is started and a blast of cooling air isdirected at the shell through the air tubes- 63 thereby quickly bringingthe backing metal to a plastic sandy condition. When the blower goes oifthe operator is signalled to transfer the shell 10 to the water cooledplaten 71 of the press 70 and he presses the button 6 to start the presscycle. The platen is moved inwardly to a position immediately above thehydraulic ram 72 and when it is in its innermost position completes acontrol circuit for the ram and causes the ram to rise upwardlythrusting the shell and cardboard backing against the water-cooledresilient pad thereby exerting an even pressure on the entire surface ofthe shell during the cooling operation. When the operation is completedthe ram retracts and the platen is returned to its original forwardposition. I

Figure 10 shows the electrical control circuit diagram for theoperations performed at the supporting table. The control circuitincludes four double relays, marked A, B, C and D, two automatic timers100, 101 together with double acting relays, one for the pump, and one101 for the blower, an electric motor 102 for driving the centrifugalblower 65, and electric motor 103 for driving the pump 31, a springbiased solenoid actuated valve 104 for valving a hydraulic fluid to thefinger actuating cylinder 61, a solenoid valve 105 for controlling theflow of gas to the heating means and a thermocouple 106 to regulate thetemperature of the heat supplied to the supporting surface 41 of thetable 40.

The control circuit must first be alerted by closing the manual switch 8which places the circuit in a starting condition and which also startsthe gas burners 42 by energizing the solenoid valve 105 through themanual switch 8, stop button 3, control line 4 (GL4), the lower relay inthe blower timer 101, through the thermocouple 106 and across to L2. Thethermocouple 106 is set to keep the temperature of the supportingsurface 41 at a level which will insure proper heating of the shell 10but which will not prevent the cooling air from quickly bringing thebacking metal to a plastic sandy state. After the operator closes theswitch 8 he places an empty electrotype shell 10 on the supportingsurface 41 and thereafter pushes control button 1. When button 1 ispushed the coil in relay A is energized closing both the relay switches.the coil thorugh GL4, the top normally closed relay in relay C, toprelay A, coil A across to L2. The closing of the bottom relay in Aenergizes the finger solenoid valve, the circuit being through GL4, thenormally closed relay in the blower timer, lower relay A, the fingersolenoid and L2. When the finger solenoid is actuated the valve 104 isthrust to its downward position and hydraulic pressure fluid is valvedto the underside of the piston in the actuating cylinder 61 and thefluid on the upper side of the piston is exhausted to the return tankthereby moving the piston upwardly and lowering the fingers 50.

' When the operator sees that the flux in the shell is ready to receivethe backing metal he pushes button 2 thereby energizing the coil of thepump timer 100 and closing the relay. The closing of the upper relaycompletes a hold ing circuit for the coil through the circuit GL4, thetiming mechanism, the upper relay in the pump timer, the coil in thepump timer over to L2. The closing of the lower relay in the pump timerenergizes the coil in relay D through the circuit GL4, the lower relayin the pump timer, coil in relay D, over to L2. When the coil in relay Dis energized both the upper and lower relays are closed, the closing ofthe upper relay completing a circuit to the pump motor through GL4, thelower relay in the pump timer, the upper relay in relay D, the pumpmotor,

over to L2. The closing of the lower relay energizes the coil in relay Dcompleting a circuit through GL4, the normally closed upper relay inrelay C, coil in relay B, the lower relay in relay D over to L2. Whenrelay B is energized the upper relay completes a holding circuit for thecoil B through GL4, the upper normally closed relay The top switchcompletes a holding circuit for in relay'C, coil B, upper relay'B, overto L2. The closing of the lower relay in B puts the blower timer coil ina condition to be energized upon the die-energizing of relay D.

When the pump timer mechanism breaks the holding circuit of the'pumptimer coil the relay of the timer is de-ene'rgized thereby de-energizingrelay D. When relay D is de-energized the lower relay assumes itsnormally closed position and completesthe blower timer circuit throughCL4, the lower relay in relay B, the blower timer coil, the lowernormally closed relay in D over to L2. The closing of the upper relay inthe blower timer completes a holding circuit for the blower timer coilthrough CL4, the timing mechanism, the upp'errelayin the blower timer,the blower timer coil, the lower normally closed relay in D, over to L2.Atthe same time, the normally cl'osed relay' in the'blower timer assumesits open position thereby de-energizing thesolenoid gas valve 105 andthe finger solenoid valve 104 turning off the gas and raising thefingers. In its open position the lower relay completes a circuitthrough coil C through CL4, the lower relay in the timer, coil C andover to L2. When relay C is energized the upper normally closed relay isbroken thereby de-energizing relay A and the lower relay in C completesa circuit to the blower motor 102 through CL4, lower relay C, the blowermotor, over to L2. After a proper interval of time the timing mechanismin the blower timer interrupts the holding circuit for the coil therebyde-energizing the relay in the blower timer and de-energizing the relayC. When the relay C is de-energized the blower motor is turned off andthe'control circuit is in condition to repeat the cycle.

If it is necessary to stop the operation of the apparatus quickly theoperator pushes the stop buton 3. When this button is pushedthe entirecontrol circuit is isolated from L1 and all operations come to a halt.Button is pushed by the operator when it is desired to operate the pumpmanually. Button 5 completes a circuit from CL3 through the upper relayD to the pump motor and operates the motor as long as the operatorcontinues to push on the button 5. Button 4 operates in a similar mannerfor the'blower, the relay C and the blower motor being energized by theoperator as long as he pushes on the'button.

The press control circuit'diagrammed in Fig. 11 includes a press timer110 with'a double relay, a single relay E, a spring biased, solenoidactuated valves 78 for controlling the flow of hydraulic fluid to theactuating cylinder for the water cooled platen 71, a second springbiased, solenoid actuated valve 80 for controlling the flow of hydraulicfluid to the piston for the ram 72, a contact 111 on the rearward end ofthe platen 71 for closing a normally opened gap 112 in the circuit atthe end of its rearward travel, a normally closed spring contact 113opened by' the hydraulic ram 72 at the limit of its downward travel, anda stop button 7 and a starting button 6. To put the control circuit in aready condition the operator first closes the manually actuated knifeswitch 9. He then places the electrotype shell 19 on the water cooledplaten 71 at the forward portion of the press 70. Starting button 6 isthen pushed to initiate the cycle of operation;

When the start-button 6' is pushed the actuating circuit for the coil inthe press timer relay is energized and both relays in the timer 110 areclosed. The closing of the top relay completes a holding circuit for thecoil from CLS, through the timing mechanism, the upper relay, the presstimer coil, and over to L2. Closing the bottom relay in the timerenergizm the relay E through the circuit, CLS, lower relay in the presstimer, coil in relay E, over to L2. Whenthe coil E is energized therelay E is closed and the coil circuit for the platen solenoid valve iscompleted from CLS, lower relay in the press timer, relay E, solenoidcoil, and over to L2. Under the influence of the solenoid the valve 78is moved downwardly to valve hydraulic fluid from the pressure line tothe right hand 8 side of the piston 79in the platen actuating cylinderand thefluid on the left hand side of the piston isexhausted' to thereturn'tank of the hydraulic system. As the piston moves leftwardly therack 77 secured thereto rotates'the pinion gear 76 which in turnrotates'the square stud 75. The stud 75 causes the slotted lever arm 73to rotate also and to move the platen 71 rearwardly toward the hydraulicram 72.

The closing of the'lower relay in the press timer also alerts thesolenoid in the ram solenoid valve 80 and puts it in a condition to beenergized upon the closing of the normally opened gap 112 in the coilcircuit. Whenthe platen 71- has moved to the limit of its rearwardtravel a contact 111- on the rearward end of the platen closes the gap112 and energizes the ram solenoid valve 84). Under the urging of'thesolenoid the valve 80 moves downwardly and valves hydraulic fluid fromthe pressure line to the underside of the ram piston 81. At the sametime fluid on the upper side of the piston is exhausted to thereturn'tank of the hydraulic system. As the piston moves upwardly toexert a pressure on the electrotype shell 10 during the coolingoperation the normally closed spring contact 113 is allowed to close.The closing of this contact 113- alerts a second holding circuit for theplaten solenoid valve 78 to be energized upon the deenergizing of thepress-timer relay and relay E thereby holding the platen in its rearwardposition during the lowering of the hydraulic ram 72.

The hydraulic ram exerts a pressure on the shell for a predeterminedtime set in the timing mechanism of the press timer 110. When the timeis up the time mechanism' de-energizesthe'press timer coil and relaysand also de-energizes relay E. When the lower relay in the press timerreturns to its normallyopened position the solenoid in the ram solenoidvalve 80 is returned to 1 its normal position by the spring andhydraulic fluid from the pressure line is valved to the top of the rampiston 81 while the fluid on the underside of the valve is returned tothe tank thereby lowering the ram to its normal position. During thelowering of the ram the platen 71 has been held in its rearward positionby the circuit GL5, normally closed spring contact 113, normally closedrelay E, solenoid coil and L2. When the ram 72 reaches its downwardlylimiting position it opens the spring contact 113 and de-energizes theplaten solenoid valve 78. The spring then returns the valve to itsnormal position, valving fluid to the left hand side of the piston andexhausting fluid from the right hand side of the piston-thereby'movingthe piston rightwardly, rotating the pinion 76 leftwardly and moving theplaten 71 to its forward position.

It is to-be understood that the form of the invention shown anddescribed is merely a preferred embodiment and that the invention in itsbroader aspects is not limited to the specific mechanisms shown anddescribed but dethe accompanying claims without departing from theprinciples of the invention and without sacrificing its chiefadvantages.

I claim:

1. Apparatus for backing-up electrotype shells including a stationaryheated, thermostatically-controlled supporting surface for theelectrotype shell, a plurality of individually movable, downwardlyacting, yieldable fingers for pressing the face of the electrotype shellin contact with said surface, a pump for supplying molten backing metalto the electrotype shell during the time the shell is held in contactwith the supporting surface, and timing means for automaticallycontrolling the volume of metal delivered by the pump.

2. Apparatus as set forth in claim 1 in which the fingers areretractable.

3. Apparatus for backing-up electrotype shells said machine including astationary thermostatically controlled supporting surface for theelectrotype shell, a plurality of downwardly pressing individuallyyieldable fingers for engagement with the shell to hold the shell incontact with the supporting surface during tthe pouring of backing metalonto the shell, supporting structure for the fingers, and blowerapparatus in said supporting structure for directing a flow of coolingair to the backing metal in the shell.

4. Apparatus as set forth in claim 3 having heating means for thesupporting surface for the electrotype shell and control means foractuating said heating means during the pouring of the backing metalonto the shell and thereafter for turning off the heating means andstarting said blower apparatus for cooling air fiow.

5. Apparatus for backing-up electrotype shells including a stationarysupporting surface for the electrotype shell, a plurality of downwardlypressing individually yieldable fingers for holding the face of theshell in contact with the supporting surface, heating means underneaththe supporting surface for the heating thereof, a pump for pumpingmolten backing metal directly onto the electrotype shell, adjustablecontrol means for automatically controlling the volume of metaldelivered by the pump, a plurality of tubes above the supporting surfacefor directing a flow of cooling air at the electrotype shell to cool thebacking metal, and a second control means for turning off the heat andfor starting and automatically timing the flow of air to the'electrotype upon the termination of pump operation.

References Cited in the file of this patent UNITED STATES PATENTSJackson Aug. 14, Ringler Apr. 23, Dunton Dec. 14, Nocheck May 16, KeefeNov. 21', Gounley Mar. 13, Eckersall Oct. 27, Slade Sept. 28, Loesser eta1. July 1, Temmen Oct. 21, Smith June 26, Bungay Dec. 5, Atwood Nov.19, Huck Mar. 25, Myers Apr. 11, Holmes et a1 Nov. 28, Tama Apr. 6,Bishop Feb. 26, Tyler Apr. 30,

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